1. Field of the Invention
This disclosure relates to an image formation apparatus.
2. Description of Related Art
In a conventional image formation apparatus, an image is developed using toner (a developer) on the surface of a photoreceptor drum, and in some cases, a part of the toner is not properly transferred and remains on the surface of the photoreceptor drum. The remaining toner is removed by a cleaning blade in a process after the process of transfer to the surface of the photoreceptor drum. However, some of the toner not removed by the cleaning blade further adheres to the surface of a charge roller on a downstream side in the rotation direction of the photoreceptor drum.
The image formation apparatus removes the toner on the charge roller by executing a cleaning mode. In the cleaning mode, a different bias from that applied in the printing process is applied to the charge roller in order to remove the toner adhered to the surface of the charge roller (hereinafter, also referred to as extraneous matter) (see Japanese Patent application Publication No. 2000-259057, for example).